Hierarchically structured nitrogen-doped carbon for advanced supercapacitor electrode materials

A facile and scalable method is used in this study for oxidation polymerization and catalytic carbonization method to prepare three-dimensional hierarchically structured nitrogen-doped carbon nanohybrids (3D N-CNs) which could be used as the efficient electrode material for supercapacitors. In the synthesis process, citric acid plays an important role in controlling the shape of nitrogen-doped carbon nanohybrids. As an electrode material for supercapacitors, the 3D N-CNs-2 possess high specific capacitance of 274.6 F g−1 at 0.5 A g−1, excellent rate capability (ca.75.5 % retention along with the current density increasing from 0.5 to 20 A g−1) in 6 M KOH aqueous solution. The electrochemical performance can be ascribed to the synergistic effects of the hierarchical nanostructure and nitrogen doping, suggesting that the 3D N-CNs-2 as novel electrode materials may have the potential applications in high-performance energy storage devices.